Recently, an increased demand for high data rates in mobile communications has been seen, and this trend will most likely continue in the coming years.
In order to meet this demand, new transmission techniques have been developed. In the forthcoming evolution of present mobile cellular standards like GSM and Wideband Code Division Multiple Access (WCDMA), Orthogonal Frequency Multiple Access (OFDM) will be used for transmission. OFDM promises higher data rates and a more efficient usage of limited bandwidth resources than the presently employed techniques.
Furthermore, in order to have a smooth migration from the existing cellular systems to a new high capacity and high data rate system in existing radio spectrum, such a new system has to be able to operate in a flexible bandwidth. A proposal for such a new flexible cellular system is 3G Long Term Evolution (3G LTE) that can be seen as an evolution of the 3G WCDMA standard. This system will use OFDM as multiple access technique (called OFDMA) in the downlink and will be able to operate on bandwidths ranging from 1.4 MHz to 20 MHz. Furthermore, data rates up to 100 Mb/s will be supported for the largest bandwidth, and such data rates will be possible to reach using MIMO (Multiple-Input-Multiple Output) schemes in the down-link.
In such a system, and in a situation where a mobile device is surrounded by a number of cells, problems relating to strong inter-cell interference (ICI) may occur. In order to optimize the throughput also in such a situation, the mobile device needs to implement methods for handling such inter-cell interference.